This invention relates to the decontamination of soils and groundwater of gasoline, caused primarily by leakage from service station storage tanks.
Efforts to reclaim areas of soil and groundwater contaminated with gasoline heretofore have involved a variety of activities following removal of gasoline storage tanks. One effort has involved the costly physical removal of the contaminated soil to substantial depths and either purifying the soil or replacing it with uncontaminated soil, sand, or gravel. Another effort involves the in situ high pressure air injection into sealed wells for lateral migration through the gasoline-containing subsurface, and the extraction of hydrocarbon vapors entrained in the resulting air stream from vacuum recovery. The effectiveness of this system is quite limited, especially in low permeability soils, primarily because of the difficulty in evenly dispersing the injected air laterally through non-homogeneous subsurface environments.